distinguish the difference between Contributory and Comparative Negligence. Please define these defenses and whether it can be used it the Commonwealth of Virginia and how It was used. This must be identified using case law. Please carry me through the history of these doctrines and how these theories have progressed in the Commonwealth of Virginia only. Provide me with a thorough analysis of how it can be used today and any exceptions is may have. Furthermore, how potentially this could affect your cases that come into your office if your clients were 20%, 40%, or 70% at fault.